In recent years, in a light emitting display device for mobile purposes, there is a strong demand for high resolution and low power consumption. Display devices which use a liquid crystal display device (LCD) or organic light-emitting diode (OLED) such an organic EL display device or electronic paper etc are being adopted as display devices for mobile purposes.
Among these, an organic EL display device does not require a back light or polarizing plate which were necessary in liquid crystal devices. Furthermore, since the drive voltage of a light emitting element which is a light source is low, these devices are attracting a great deal of attention as low power consumption and thin light emitting display devices. In addition, since it is possible to form a display device just with a thin film, it is possible to realize a display device capable of bending (flexible). Furthermore, since these display devices do not use a glass substrate, they are attracting a great deal of attention as display devices which are light and difficult to break. In particular, in a organic EL display device of a medium/small size, high definition of a display part is required. For example, with the progress in high definition display devices, because the space between adjacent pixels becomes narrow, the amount of light leaking from an end part of a pixel which reaches an adjacent pixel increases. When light generated in a pixel is emitted to the exterior from an adjacent pixel, problems such as a drop in definition or bad color reproduction occur.
In an organic EL display device, light is emitted by flowing a current to a light emitting element of a light source. The light which is emitted from a light emitting element proceeds to the side of a viewer via a different layer. However, a part of the light is reflect at the interface where different layers contact, is wave guided through a layer, is transmitted to a pixel adjacent to a pixel which is to supposed to emit light and is emitted to the exterior from the adjacent pixel, which leads to what is called leaked light. In particular, in high definition display devices which exceed 300 ppi, among the light generated in a light emitting element about 80% is lost due to wave guiding through each layer as described above.
Therefore, in patent document 1 for example, in the case where a white light organic EL element and color filter type are used, a technology is disclosed in which leaked light is controlled between each pixel by arranged a light shielding layer between each color filter which controls a reduction in color reproduction. However, in the structure disclosed in Japanese Laid Open Patent 2012-163651, a part of the light emitted in the direction of a viewer from a light emitting element is absorbed in the light shielding layer which leads to a drop in light emitting efficiency.